22 caliber conversion for a colt 45 caliber semi-automatic pistol



w. B. RuGl-:R 2,898,693 22 CALIBER CONVERSION FOR ACOLT 45 CALIBER SEMI-AUTOMATIC PISTOL 1 Filed April 17. 1956 Aug. l1, 1959 7 r ljess Mia/rma I INVENTOR FIG. 4 WILLI-AMB. RUGER BY l f ATTORNEYS United States Patent @dice 22 CALIBER CONVERSION FO'R -.COLT 45 CALIBER -SEMI-AUTOMATI-C TPIS'IOL William B.. Ruger, Westport, Conn., fassignor .to Sturm,

Ruger and Company, Inc., Southport, Conn., a ,corporation of Connecticut Application April 17, 1956, Serial No. 57857257 Y 1 Claim. y(Cl. 42-77) This invention -relates to the semivantomatic pistols commonly known as .the .Browning.or Colt, and has for .its object .the provision of an improved .-22 caliber conversion :for such pistols. While the ,invention is primarily and .mostadvantageously adapted to the .45 caliber United States Army embodiment of the Browningserniautomatic pistol, usually called the. fColt 145, itgis `to be understood that the invention `applies to any .of .the various large calibers of such pistols, which aretcharacterized by having a breech block, commonly called la slide, reciprocally mounted on a grip amember, and a barrel which is connected Aby a linkage to the `grip member, said ,slide being .lockedby lugs to the barrelat the time of ring. During recoil, `the barrelmoves `a short distance in coupled connection .withthe `slide and the linkage unlocks the .barrel ffronrthe :slide. (.Hereinafter, for convenience, such pistols vwill be called ithe fColt 45 `or .Colt 45 caliber type.) This Colt pistol is .described :and illustrated .in the patent of John M. Browning No. 580,924 yand in .the Williams.PatentdtltnA 2,090,657.

The 22 caliber conversion tof ,my 1inventituxprovides a 22 ,caliber barrel `which Ais operatively Aglixed ltu but removable from, .the grip member, :a `breech voc-Y sf ing or receiver which `is. slid tinto enga-gement. withbtlie grip member during assembly in the manner of the original slide but .which is Asecured :in ,its .operative posif.

tion to `the barrel and indirectly to the grip member, and a blow-back vbreech :block rwhich -is mounted in the receiver. The conversion utilizes the .mechanism Ain the grip member and includesa magazine ,for g caliber short or long-rie cartridges and, aQQQLdinglyg `ouverts the saidlarge caliber pistol into a 2 2lcaliber blowback semi-automatic pistol. Y

ThetColtAS and like embodiments `of the Aliront/'nin pistol have a llink yand cross-pin whichconnect -the'ba-rrel to the grip member and another cross-pin known as the slide stop which passes through the grip member and limits the movement of the slide.

In my invention I provide a barrel having a depending lug having a hole or recess by means of which the barrel is secured in its xed position to the grip member by the slide stop. The barrel is mounted in the receiver and is secured to the receiver as by means of a nut.

One important feature of the invention is the construction and arrangement of the breech block in relation to the reeciver `and barrel by means of which I may, with considerable advantage, construct both the breech block and receiver of a light metal such as aluminum. The breech block reciprocates in the receiver and in its most rearward position projects beyond the rear end of the receiver. In this reciprocable motion cartridges are fed into the barrel, the empty cases are extracted and ejected and the hammer is cocked. The breech block is provided with an elevated shoulder which engages an abutment on the reeciver to arrest the rearward travel of the breech block. When the receiver is made of v2,898,693 Patented VAug. 1 -1 1959 2 aluminum, 4the receiver has a .steel cross pin which Serves `as an abutment to stop vthe 4breech block ywithout injuring the receiver. This construction gives the ad* vantage of using a steel pin to absorb the blow and `in that -fway rfurther enables me to use aluminum for these members.

To facilitate the take-down and assembly of the entire conversion the receiver is provided `with guide ribs which engage grooves inthe grip member and the receiver is merely `slid `into position. A return coil -gspring is mounted over :the .barrel and .connected by a rod to the breech block. The rod has a hooked end which engages a slot in the breech block and .the conversion'can be assembled by inserting the 4barrel with its surrounding return spring and lthe rod and breech block into the receiver andsecuring-the barrel to the receiver by anut. 'This conversion u nit is .then slid onto the grip member and is secured in place .by inserting the slide stop through the holein the grip member and the recess in ,theflug von the barrel. The barrel is thus secured to the grip member, the receiver issecured ito the Vbarrel and -the lbreech block canreciproca-teinthe receiver'as a-true blow-back -breechbloclc In athe accompanying drawings:

Fig. l is a side elevation of a nsemi-automatic pistol embodying the invention; y

Fig. 2 is a vertical `sectional view on an enlarged scale ofthe upper `portion of the pistol of "Fig l1 lillustrating the 22 caliber conversion of the invention;

t {Eigy 3 iS a fragmentary portion of.;Fig 2 illustrating then rwardposition of the breech block;

iEig. :4 is a view-from` above of the pistol of Fig. 1 `with Parts shofwmin .cross-Section;

Fig. 5 fis.a `sectionalview'at 5 5 O fFig. 2; and

Egf 6 v-iS an end view of the breech Vblock with parts removed.

The drawings 'show in full lines ,theelements comprisingythe Zicaliber conversion @of the invention inoperatiyegconnection with a standard ,grip -memberof a Colt aliber z semi-:autoinatic pistol .shown .in broken zlines.

Lconversion unit or assembly of the linvention comprisesffa receiver 1 .Which :iS in Slidabl .Connection With the grip fmember 2 :andi is;supported in guided ,connection hleto by A the longitudinal ribszfand 4 whiehengage tilesdeigi'oovcs Stand `lzon lthe grip member. This reeeiuerghas `thegeneral shape and dimensions` ofthe slide offtlle usual Colt-45, fandfgvesthegeneral exteriorappearance of that pistol. In view of the relatively great weight of.tfheColt 45 it isadvantageous to constructthe receiver of a light metal such as aluminum! or-analuminum alloy. 'Ehe forwand portion of the receiverhas anopening 7 the barrel 8. The rearward portion of the receiver is also open, being generally rectangular in cross-section and receives the breech block 9.

The barrel 8 has a threaded forward end 10, a small diameter portion 11 and a depending lug 12 which, as shown, is ldriven into la slot 13 in the barrel and is accordingly secured in =a Xed position. The lower portion of the lug has a recess 14 for receiving the standard crosspin 1S of the Colt 45 and the barrel is accordingly keyed to the grip member. The nut 16 secures the receiver to the barrel.

The breech block 9 may be made of any suitable metal, preferably aluminum, and is Iformed to move forward or rearward during action and is accordingly what is known as a blow-back breech block. The under surface of the breech block is cut out at 17 to provide clearance lfor the magazine 18. It also has a cut out 19 to operate the standard trigger disconnector 20 which is mounted in the grip member of the Colt 45. The -breech block has a longitudinal slot 21 in which is mounted a flat ring pin 2.2. The firing pin is held in its rearward position out of contact with the cartridge by the rebound -spring 23 and follower pin 24. The forward end of the iiring pin is held in position by a cross pin 25 in the breech block which passes through an elongated slot 26 in the firing pin. The rearward end of the tiring pin is held in position by the steel insert 27 through which it projects. By pushing the tiring pin forward the steel insert 27 may be lifted upward. This insert receives the blow of the hammer and prevents damage to t-he aluminum breech block.

The forward end of the breech block has a transverse slot 28 in which is mounted a lateral hook 29 on the return rod 30 which returns the breech block to its closed position. It will be noted that the breech block in its closed position, as shown in Figs. 1 and 4, extends through to the end of the receiver and is ush with the face of the hammer 32 in tiring position. As best shown in Fig. 4 the breech block has laterally extending lugs or ears 34 and 35 for hand gripping to pull the breech block rearward and operate it manually. The rearward portion of the receiver has a cross pin 36 formed of a hard metal, such as steel, which enters the space traveled by the breech block. The lbreech block has anl upwardly projecting shoulder 37 which bears against the top of the receiver and which also provides a stop for engaging the steel cross pin 36 to stop the rearward travel of the breech block, as shown in Fig. 3.

The breech block has a cartridge extractor 40 of a wellknown type and the empty cartridge cases are ejected through the port 41 by striking the projection 42 on the top of the magazine.

The small diameter portion of the barrel 11 is surrounded by the return spring 38 which bears at one end against a shoulder 39 on t-he barrel and at the opposite end on a collar 40 that loosely surrounds the barrel and which is attached to the return rod 30. The threaded end of the barrel projects beyond the forward end of the receiver and is secured in position by the nut 16. It is to be understood that thev grip member 2 comprises the hammer, hammer spring, safety, sear, sear spring, trigger assembly, magazine catch and trigger disconnector of the standard Colt 45. While the grip portion is constructed to receive a magazine for the larger caliber cartridges this standard magazine is replaced 'wit-h a magazine having similar exterior dimensions but lwhich is modiied to receive either 22 caliber short or 22 caliber long rille ammunition. The modied magazine shown comprises a band 45 which has a recess 46 on one side which engages the standard magazine catch and release 47.

The 22 caliber conversion of the invention is mounted on a Colt 45 as follows:

The slide is set in the proper position and the slide stop is removed. rfhis enables one to remove the slide and barrel from the grip member. The receiver 1 is held in an upside down position and the barrel, return spring 10, collar 38, and return rod 30 are inserted in the receiver in the position shown, and the nut 16 is screwed on to a point Where the hook 29 projects into the receiver. The breech block 9 is t-hen inserted into the receiver to the position shown in Fig. 2. The receiver is turned over and slid into position on the grip member. The longitudinal ribs 3 and 4 of the receiver engage the side grooves 5 and 6 on thevgrip member and the receiver is accordingly held in a slidable position on the grip member. By adjusting the nut 16 the recess 14 on the lug 12 is moved into coincidence with the hole on the grip member and the slide stop is inserted through the hole. The nut 'can then be tightened to press the receiver tightly against the ysteel plug 49 and the receiver and barrel are in their rigid fixed operative position. While the steel plug may be omitted to allow the aluminumof the receiver 1 to engage the lug 12, the steel plugprovides a more wearable surface. The standard slide stop has a lateral arm 50 with an inwardly projecting lug that is pushed through an opening in the grip member and the cut-out 53 on the receiver. In the standard Colt 45, the slide stop is held in position on the side of the grip member (not shown), but in this conversion, the pressure exerted by the nut 16 holds the slide stop in an immovable position.

I claim:

1. A 22 caliber conversion for a Colt 45 caliber semiautomatic pistol from which the slide and barrel have been removed, lwhich comprises a grip member having a hammer mounted thereon, a cross-pin which passes transversely through the grip member, a receiver which is interchangeable with the slide attached in a fixed operative position on the grip member, a 22 caliber barrel mounted in the receiver and removably 1secured to the grip member by the {cross-pin, a blow-back breech block in the receiver which travels rearward on firing and cocks the hammer, a return spring in the receiver, means connecting the return spring to the breech block, and means securely connecting the receiver and barrel together, whereby Vsaid 22 caliber barrel and receiver are held in fixed position with respect to the grip member.

References Cited in the le of this patent UNITED STATES PATENTS 

